How can I attach a top plate for a wall that falls between joists?

Question

I have a wall that I need to build to make a defined space for a laundry room. I am running into 2 problems with my project:

1. I have a slanted ceiling, and
2. The wall will be going parallel to the joists.

I have read that I need to add nailing block to the ceiling; however (admittedly, looking for a short cut here), I was hoping maybe I could avoid cutting into the ceiling by accessing the attic above, installing the blocking, and then attaching the top plate (hopefully that is the right terminology) to the ceiling? I think I can mud the wall, but the ceiling is textured, and I want to avoid having to re-texture as much as possible.

Answer 1

You plan is sound. You really only need blocking every four feet or so, and at each end. The rigidity in your top plate will keep things from moving if it's securely attached to the blocking.

If, by chance, you have no insulation in the attic you could install blocking from below. Cut some 3" by 8" slots in the drywall inside the wall line for access, and insert the blocks through there. Install them either spanning the slot or adjacent to it.